[volt-nuts] Trimming the LTZ1000 tempco

[Will]

I would take the output voltage between pins 3 and 7 and leave the
resistor "outside". There is already a diode between the op-amp output
and the zener cathode and the diode must be much less time and
temperature stable than a resistor.

Or did I misunderstand something again?

Will


2011/10/7, Andreas Jahn <Andreas_-_Jahn at t-online.de>:
> But consider: a resistance change on the 200R resistor of page 6
> will directly affect output voltage. 200R * 5mA = 1V.
> A 100 ppm change of the 200R Resistor has a 1V/8.2V
> = 12 ppm change on output voltage.
> All other resistors have below 1ppm change with 100ppm resistance change.
>
> So the 200 Ohms resistor will be the most
> critical for tempco and ageing in the whole system.
>
> So in my opinion its only worth to consider if you
> really need to save the 20-30 mA for the heater.
>
> With best regards
>
> Andreas
>
>

>